From b1054282d752c5a026e2c0450616ebf37fc0413e Mon Sep 17 00:00:00 2001 From: Tkhai Kirill Date: Tue, 10 May 2011 02:31:41 +0000 Subject: sparc32: Fixed unaligned memory copying in function __csum_partial_copy_sparc_generic When we are in the label cc_dword_align, registers %o0 and %o1 have the same last 2 bits, but it's not guaranteed one of them is zero. So we can get unaligned memory access in label ccte. Example of parameters which lead to this: %o0=0x7ff183e9, %o1=0x8e709e7d, %g1=3 With the parameters I had a memory corruption, when the additional 5 bytes were rewritten. This patch corrects the error. One comment to the patch. We don't care about the third bit in %o1, because cc_end_cruft stores word or less. Signed-off-by: Tkhai Kirill Signed-off-by: David S. Miller --- arch/sparc/lib/checksum_32.S | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) (limited to 'arch') diff --git a/arch/sparc/lib/checksum_32.S b/arch/sparc/lib/checksum_32.S index 3632cb34e914..0084c3361e15 100644 --- a/arch/sparc/lib/checksum_32.S +++ b/arch/sparc/lib/checksum_32.S @@ -289,10 +289,16 @@ cc_end_cruft: /* Also, handle the alignment code out of band. */ cc_dword_align: - cmp %g1, 6 - bl,a ccte + cmp %g1, 16 + bge 1f + srl %g1, 1, %o3 +2: cmp %o3, 0 + be,a ccte andcc %g1, 0xf, %o3 - andcc %o0, 0x1, %g0 + andcc %o3, %o0, %g0 ! Check %o0 only (%o1 has the same last 2 bits) + be,a 2b + srl %o3, 1, %o3 +1: andcc %o0, 0x1, %g0 bne ccslow andcc %o0, 0x2, %g0 be 1f -- cgit v1.2.3-59-g8ed1b